The present flat-bed knitting machines in which the carriage assembly is taken along or, alternatively, moved by means of a rotating chain drive actuated by a motor, lift reversal is always performed in a guided manner at the ends of the needle beds or, alternatively, on the other side of their needle areas.
However, later developments in a flat-bed knitting machines are directed towards the use of a reversible drive motor for the back and forth (reciprocal) movement of the carriage assembly in such a way that by control of the drive motor lift reversal can take place not only at the ends of the needle bed arrangement, but also at any location within the needle areas of the needle bed arrangement. Lift reversal means that the carriage arrangement must be braked ahead of the reversing point from its working speed to zero and then accelerated again to working speed. Depending on the working speed and the mass to be braked or accelerated, a fixed amount of time must be made available. Therefore it is has been proposed, starting at the respective end of the knitted material to be produced, to perform a change in the speed of the carriage assembly to zero within a set time.
However, such a time-dependent speed regulation has the disadvantage that it is never possible to reach an exactly defined reversing point on account of values which cannot be precisely determined, such as friction and the like. But a defined reversing point is of fundamental importance in connection with certain functions of the machine, such as, for example, the casting off or, turning off of yarn guides which should always be positioned at a defined location, or the like. Also, in connection with, for example, double or multiple head machines it is important to perform lift reversal in such a way that on the one hand the last head is moved out of the needle area of the needle bed arrangement in which work has been completed and the first head is moved into the needle area of the adjacent material in an exactly defined manner. In case of an indefinite or, respectively, not exactly reproducible reversing point there is the danger that the carriage is moved too far or not far enough.